From the Guidelines
The best treatment for an obstructing urethra stone is ureteroscopy (URS) due to its high stone-free rates and low complication rates, as demonstrated in the 2007 guideline for the management of ureteral calculi 1.
Key Points
- URS has become a safer and more efficacious modality for treatment of stones in all locations in the ureter, with overall stone-free rates of 81% to 94% depending on stone location 1.
- The development of smaller caliber semirigid and flexible ureteroscopes and the introduction of improved instrumentation, including the holmium:YAG laser, have contributed to the enhanced success of URS 1.
- Complication rates, most notably ureteral perforation rates, have been reduced to less than 5%, and long-term complications such as stricture formation occur with an incidence of 2% or less 1.
- URS is associated with a better chance of becoming stone free with a single procedure, but has higher complication rates compared to shock-wave lithotripsy (SWL) 1.
Treatment Options
- URS is recommended as a first-line treatment for patients requiring stone removal, due to its high stone-free rates and low complication rates 1.
- SWL is also an acceptable first-line treatment, but has lower stone-free rates and higher re-treatment rates compared to URS 1.
- Other treatment options, such as percutaneous nephrolithotomy (PCNL), laparoscopic, open, or robotic-assisted stone removal, may be considered in patients who fail or are unlikely to have successful results with SWL and/or URS 1.
Special Considerations
- In patients with obstructing stones and suspected infection, urgent drainage of the collecting system with a stent or other means is necessary 1.
- Patients should be counseled on the attendant risks of medical expulsive therapy (MET) and should be informed that it is administered for an “off label” use 1.
From the Research
Management of Obstructing Ureteral Stones
The management of obstructing ureteral stones can be approached through various methods, including ureteroscopy (URS), shockwave lithotripsy (SWL), stent placement, and percutaneous management.
- URS is the predominant modality used for urgent treatment of acute proximal ureteral stones, except for larger stones where percutaneous management is preferred 2.
- Immediate URS is the preferred choice for all distal and midureteral stones, regardless of size 2.
- The use of stents vs percutaneous nephrostomy drainage is similar for proximally obstructing calculi, while stent insertion is preferred over nephrostomy for mid and distal stones 2.
Comparison of Management Options
Studies have compared the efficacy of different management options for obstructing ureteral stones.
- A study comparing Extracorporeal Shock Wave Lithotripsy (ESWL) and Ureterorenoscopic Lithotripsy (URSL) found that both methods are equally effective in the management of upper ureteric calculus, with no significant difference in age, male/female ratio, stone diameter, and stone-free ratio 3.
- Another study evaluating the emergency management of obstructing ureteral calculi with two different techniques (SWL and URS) found that URS may be applied more effectively, with the advantages of prompt fragmentation of the calculi, immediate relief of obstruction and pain, and better quality of life for patients 4.
Timing of Intervention
The timing of intervention, such as stent placement, can impact outcomes in patients with obstructing ureteral stones and presumed infection.
- A study found that timelier stent placement (within 6 and 10 hours of ED arrival) is associated with a significantly decreased length of stay (LOS) in patients with obstructing ureteral calculi and concern for infection 5.
- The study also found that there was no difference in the need for ICU admission between groups, but the overall LOS was significantly decreased in patients who underwent stent placement within the specified time intervals 5.
Antibiotic Usage
The use of antibiotics in the management of obstructing ureteral stones is also an important consideration.
- A study evaluating the current management of patients with obstructive ureteral stones in a single ED found that antibiotics were given at the discretion of the provider without a clear pattern, and a high rate of infectious complication did not occur in the followed-up patient group 6.